1.Technical Field
This invention relates in general to processing magnetic recording media during fabrication, and in particular to an ESD-sensitive, corrosion-free system for cleaning all types of contamination from the surfaces of rows of magnetic recording media while fabricating the rows into magnetic read/write heads.
2. Description of Related Art
During the fabrication of thin film, magnetic read/write heads for magnetic recording applications, the heads are formed from a continuous row on a media wafer.
Each wafer typically contains hundreds of rows, and each row may produce hundreds of heads. The rows are processed from the wafer prior to being segmented into the individual heads. The rows must undergo thorough and difficult cleaning processes prior to each of the critical fabrication steps, only a few of which are described above.
There are at least two major factors that contribute to the difficulty of cleaning rows. The first factor is the complex topography of the rows. Each of the heads on each row has a very precise air bearing surface (ABS) pattern that has been reactive ion etched (RIE) or ion milled thereon. ABS comprise intricate three-dimensional contours on the side of a head that will fly adjacent to a disk. The second factor is the assortment of surface present on the rows during the various fabrication steps. Contaminations such as particulates, stains, adhesives, residual photo resist, laser slag, and chemical and/or environmental contaminants are common.
Current cleaning technology employs several different cleaning strategies, including high or low pressure sprays, mechanical brushes, ultrasonic or megasonic baths, hand spot cleaning, acoustic cleaning, carbon dioxide (CO2) or snow cleaning, and chemical cleaning. Unfortunately, no combination of cleaning techniques will consistently remove all types of contamination. Moreover, some types of cleaning tend to create or conduct electrostatic discharge (ESD). ESD can damage or destroy the rows and future heads if it is not controlled during cleaning. In addition, some cleaning strategies are very aggressive and/or abrasive, thereby mechanically damaging the row and/or corroding the device, thereby destroying the head surfaces and/or the head electronics. Thus, there is a need to develop a high through-put, non-contact cleaner that consistently will remove all process contamination from the product without causing incidental damage to the product.
A system having an array of nozzles is used to clean fabricated rows of magnetic heads. Each nozzle contains a pair of concentric tubes. The inner tube of the nozzle discharges a plume of fine dry material at a target. The outer tube of the nozzle simultaneously discharges a hollow tube of water that completely surrounds the plume discharged by the inner tube. This nozzle design prevents the dry material from mixing with the water during discharge so that the plumes remain dry until they strike the target with the tubes of water. As the nozzles pass over various portions of the target, the plumes remove most forms of process contamination, while the water serves multiple purposes. The leading stream of water in front of each plume loosens some contaminants and moistens the target prior to contact by the dry material. In addition, the trailing streams of water flush the target and removes any remaining contamination left behind after the plumes pass by. The tube of water for each nozzle also reduces dry powder overspray or dust and provides ESD protection for the target. A final rinse with a set of fan nozzles removes any residual contamination and/or cleaning media.
Accordingly, it is an object of the present invention to provide an improved cleaning system.
It is an additional object of the present invention to provide processing of magnetic recording media during fabrication.
It is yet another object of the present invention to provide an ESD-sensitive, corrosion-free system for cleaning all types of contamination from the surfaces of of magnetic recording media while fabricating the rows into magnetic read/write heads.
The foregoing and other objects and advantages of the present invention will be apparent to those skilled in the art, in view of the following detailed description of the preferred embodiment of the present invention, taken in conjunction with the appended claims and the accompanying drawings.